(a) Field of the Invention
This invention relates generally to an intelligent battery device and more particularly to an intelligent battery device where a battery pack and a battery management unit are formed, respectively.
(b) Description of the Related Art
A battery management unit is an interface between portable electronic equipment and a battery, used as a power supply. This unit has been developed for supplying information about the remaining capacity and deterioration of the battery to the portable electronic equipment, and for optimum charge control and removal of memory effect, so that the battery performance can be fully used.
An intelligent battery device, including a battery management unit and a battery as a power supply, measures the battery voltage, charge/discharge current, and battery temperature to detect the remaining capacity and control the charge. It also has a function for transferring battery and charge information through serial communication in response to the requirements from portable electronic equipment.
FIG. 1 is a schematic diagram showing the portable electronic equipment using a conventional intelligent battery device.
As shown in FIG. 1, the portable electronic equipment, having a conventional intelligent battery device therein, includes an adapter 1 and host equipment 5. The adapter I receives power from an external power supply and then outputs a constant voltage and current. The host equipment 5 operates by power from the adapter 1 or the intelligent battery device 3, and also outputs power from the adapter 1 to charge the intelligent battery device 3.
FIG. 2 is a block diagram, showing the conventional intelligent battery device. FIG. 3 is a perspective view of the device.
As shown in FIGS. 2 and 3, the intelligent battery device 3 of the portable electronic equipment, having the conventional battery device therein, comprises a battery group 7, a thermistor 9 and a battery management unit 11. The battery group is chargeable and dischargeable. The thermistor 9 measures the temperature of the battery group 7 and outputs the result. The battery management unit 11 supplies information about the remaining capacity and deterioration of the battery group 7 to the host equipment 5 and controls charge/discharge between the host equipment 5 and the battery group 7
Here, a battery pack, having the battery group 7, the thermistor 9 and the battery management unit 11 therein, is equipped within the portable electronic equipment.
The battery management unit 11 includes a charge/discharge unit 13 and a controller 15. The charge/discharge unit 13 provides a path of charge/discharge current between the host equipment 5 and the battery group 7, and outputs a voltage of the battery group 7 and a charge/discharge current. The controller 15 receives a voltage from the battery group 7, a charge/discharge current from the charge/discharge unit 13 and the temperature of the battery group 7 from the thermistor 9, and, detecting the remaining capacity and deterioration of the battery group 7, transfers this information to the host equipment 5, so that the controller 15 can control the charge/discharge unit 13.
If the adapter 1 doesn't supply power to the host equipment 5, it is operated by power from the battery group 7 connected to the battery management unit 11.
At this point, the charge/discharge unit 13 detects the voltage or current from the battery group 7 and then transfers the detected information to the controller 15. The controller 15 detects the remaining capacity of the battery group 7 by the transferred information and transfers the detected information to the host equipment 5, so that the user knows the remaining capacity.
Also, the thermistor 9 detects the temperature of the battery group 7 and then transfers the information to the controller 15, and the controller 15 detects information about the deterioration of the battery group 7 and then transfers this information to the host equipment 5.
If the remaining capacity of the battery group 7 is low, the battery group 7 is charged by the external power supplied through the adapter 1.
At this point, if the operation of the host equipment 5 is OFF, the output voltage from the adapter 1 is supplied to the battery group 7 via the host equipment 5 and the charge/discharge unit 13.
However, if the operation of the host equipment 5 is ON, the output voltage from the adapter 1 is supplied to the battery group 7 and the host equipment 5 simultaneously.
The controller 15 receives the current or voltage from the charge/discharge unit 13 and then controls the above-identified charge process.
However, according to the conventional art, because the battery management unit 11 and the battery group 7 is equipped within the battery pack 16, if liquid leaks from the battery group 7 due to a hot and humid climate and thereby damages the parts and circuit substrate within the battery pack 16, there is a possibility that the battery management unit 11 could malfunction wrong. operated, and also the battery pack 16, including the battery management unit 11, must be entirely replaced to change the battery group 7, to thereby increase the change cost.